[3] He graduated at a high school in 1960, in which Kotter attended at the University of Illinois.

[3] He served as a team manager at the Mount Vernon Senior High School.

[3] Kotter lived in Mount Vernon, Indiana during the Paralympic Games,[3] being 21 years old.

[5] Kotter was awarded the gold medal in the Columbia round open event.

[5] Kotter also participated in the Columbia round team open event along with archers, Bob Hawkes and George Pasipanki, being awarded the gold medal.